How often should I water a Christmas cactus?

Water when the top 2 to 3 cm of soil is dry, often every one to two weeks during growth and flowering. Unlike desert cacti, it prefers lightly moist soil while growing. Water less for about a month after flowering, but never let it shrivel.

How do I get my Christmas cactus to bloom?

From early autumn, give it six to eight weeks of long nights (about 12 to 14 hours of uninterrupted darkness) and/or cool nights around 10 to 16 °C (50 to 60 °F), with slightly less water. Flower buds form under these conditions.

Why are the buds falling off my Christmas cactus?

Bud drop is usually caused by sudden changes, such as moving the plant, draughts, heat, a big temperature swing, or very dry or very wet soil. Once buds form, keep the plant in the same spot with steady conditions.

Is my plant a Christmas cactus or a Thanksgiving cactus?

Look at the stem segments. Thanksgiving cactus (Schlumbergera truncata) has pointed, claw-like teeth on the edges. True Christmas cactus (Schlumbergera x buckleyi) has rounded, scalloped edges. Easter cactus has bristly, rounded segments and star-shaped flowers.

Is Christmas cactus toxic to cats?

No. The ASPCA lists Christmas cactus as non-toxic to cats and dogs, although eating a lot of the fibrous plant can cause mild stomach upset.

Christmas Cactus Care: Blooms, Watering and Light

Christmas cactus care is different from desert cactus care. These holiday cacti (Schlumbergera) come from humid mountain forests in south-east Brazil, where they grow on trees and rocks in dappled shade. So they like bright, indirect light, a light and airy mix, and soil that's kept lightly moist while growing. The key to the yearly flower show is simple: long, dark nights and cool temperatures in autumn. Cared for well, they live for decades and are often handed down through families.

Christmas cactus care at a glance

Need	What works	Avoid
Light	Bright, indirect; some morning sun	Hot midday sun (leaves redden and scorch)
Water	When top 2–3 cm is dry during growth	Soggy soil; letting it dry for weeks
Soil	Free-draining mix with bark, perlite or orchid bark	Dense compost; pure cactus grit
Temperature	16–24 °C (60–75 °F); cool nights in autumn	Heat sources, draughts
Humidity	Average to moderate	Very dry air near radiators
Feeding	Balanced feed monthly spring to late summer	Feeding while buds form
Pets	Non-toxic (ASPCA)	—

Christmas, Thanksgiving or Easter cactus?

Type	Botanical name	Segment edges	Flowers	Typical bloom time
Thanksgiving cactus	S. truncata	Pointed "claws"	Held horizontally, yellow pollen	Late autumn
Christmas cactus	S. × buckleyi	Rounded, scalloped	Hang down, pink-purple pollen	Early winter
Easter cactus	Rhipsalidopsis gaertneri	Rounded, with bristles	Star-shaped, open flat	Spring

Most plants sold as "Christmas cactus" are actually Thanksgiving cacti, because they flower earlier and are easier to time for holiday sales. Care is almost identical for both. Easter cactus needs a cooler, drier winter rest.

Light

Bright, indirect light suits them best: an east window, or a few feet back from a south or west window. A little morning sun is fine. Too much sun turns segments red or purple and can scorch them; too little light gives weak, floppy growth and few flowers. In summer, many growers move them to a shaded spot outdoors, then bring them in before nights drop below about 10 °C (50 °F).

Watering

During growth and flowering, water when the top 2 to 3 cm of soil is dry. Water thoroughly and let it drain.
After flowering, let the soil dry a little more for about four to six weeks as the plant rests.
From spring, return to regular watering as new segments grow.
In early autumn, water slightly less to help trigger buds, but don't let the plant shrivel.

Limp, wrinkled segments can mean either too little water or rotted roots from too much, so always check the soil and roots. See overwatered plant signs.

Soil and pots

Holiday cacti like an airy mix that holds a little moisture. A good recipe is two parts indoor potting mix, one part perlite and one part orchid bark. Plain cactus mix alone can be too dry. They flower well slightly pot-bound, so repot only every two to three years, in spring after flowering, and only one pot size up. A pot with drainage holes is essential. Use the soil mix calculator to make a batch.

How to get a Christmas cactus to bloom

Flower buds form in response to long nights, cool temperatures, or both. The University of Minnesota Extension explains that buds set with either cool nights of about 10 to 16 °C (50 to 60 °F) or long nights of about 13 hours or more of darkness.

Step-by-step bloom plan

When	What to do
Mid-September to early October	Start giving 12–14 hours of uninterrupted darkness each night (an unused room, or cover with a box)
Same period	Keep nights around 10–16 °C (50–60 °F) if possible
Same period	Water a little less and stop feeding
When buds appear (6–8 weeks)	Return to normal light and room, then don't move it
While in bud and bloom	Keep watering evenly; avoid draughts and heat
After flowering	Rest with slightly less water for a month or so

Street lights, lamps and TVs can interrupt the dark period, which is a common reason indoor plants fail to flower. A cool, dark spare room is ideal.

Bud drop

Holiday cacti are famous for dropping buds. Common causes:

Moving the plant once buds form, which changes the light direction.
Draughts from doors, or hot air from heaters.
Sudden temperature changes.
Soil too dry or too wet.
Low humidity in very dry rooms.

Once buds are the size of a rice grain, pick a spot and leave the plant there until it finishes flowering.

Feeding

From spring until late summer, feed every three to four weeks with a balanced houseplant fertiliser at half strength. A fertiliser that includes magnesium and trace elements is a good choice, because pale, yellowish segments on an otherwise healthy plant can point to a nutrient shortage after years in the same pot. Stop feeding in early autumn while buds are forming. Use the fertilizer dilution calculator for exact amounts.

Pruning

Prune in late spring, after the rest period, by twisting off one to three segments at the joints from the ends of stems. This encourages branching and more flower buds, since flowers form at the tips of segments. Use the pieces for propagation.

Propagation

Christmas cacti are among the easiest plants to propagate.

Twist off a piece with two to four segments.
Let it dry for a day or two so the end calluses.
Plant upright, pushing the bottom segment about a quarter of its length into slightly moist mix.
Keep in bright, indirect light and water lightly when the top of the mix dries.
Roots form in two to four weeks; new segments follow.

Plant several cuttings in one pot for a fuller plant. See how to propagate houseplants.

Common problems

Symptom	Likely cause	Fix
Limp, wrinkled segments, dry soil	Underwatering	Water thoroughly
Limp segments, wet soil, dark base	Root rot	Trim rot, repot, re-root healthy segments
Red or purple segments	Too much sun or cold stress	Move to softer light
Segments dropping	Over- or underwatering, sudden changes	Check soil, keep conditions steady
No flowers	Too much light at night, too warm in autumn	Long dark nights and cool temperatures
Bud drop	Moving, draughts, temperature swings	Keep in one steady spot
White fluff at joints	Mealybugs	See mealybugs on plants
Tiny flies around soil	Fungus gnats	See fungus gnats in houseplants

Year-round care calendar

Season	Care
Winter	Flowering; steady watering; then rest after blooms fade
Spring	Resume watering and feeding; prune and propagate; repot if needed
Summer	Bright shade indoors or outdoors; regular water and feed
Autumn	Long nights and cool temperatures; less water; no feed

Taking a plant outdoors for summer

Many holiday cacti flower better after a summer outdoors in bright shade, such as under a tree or on a covered porch. Move them out once nights stay above about 10 °C (50 °F), keep them out of direct midday sun, and water more often, since pots dry faster outside. Check for pests before bringing them back in. The natural shortening of days and cooler nights in early autumn often sets buds without any extra effort.

Christmas cactus and pets

The ASPCA lists Christmas cactus as non-toxic to cats and dogs. That makes it one of the best flowering gift plants for pet homes, unlike lilies, amaryllis and cyclamen. Check others with the plant toxicity checker and see pet-safe houseplants.

Quick checklist

Bright, indirect light
Water when top 2–3 cm is dry while growing
Airy mix with bark and perlite
Long dark nights and cool temperatures from September
Don't move it once buds form
Prune and propagate in late spring

Sources and further reading

University of Minnesota Extension: Holiday cacti, for blooming conditions and identification.
University of Florida IFAS Gardening Solutions: Christmas cactus, for growing conditions.
ASPCA Toxic and Non-Toxic Plants list, for pet safety.